Radiation fin structure for rod-like heating elements



April 24, 1962 c; M. BUTTNER 3,031,171

RADIATION FIN STRUCTURE FOR ROD-LIKE HEATING ELEMENTS Filed March 22,1960 "!'l 5 O J A910 /5. o o O O imiwmmu H w W 1% an: mm H i IN VEN TOR.(424 M (form/5e,

ATTOEN 5%- United States Patent Ohio Filed Mar. 22, 1960, Ser. No.16,739 Claims. (Cl. 257262.19)

This invention relates to a radiation fin structure for rod-like heatingelements. Electric heating elements in the shape of a rod are well knownand are used in many fields such as electric ranges and the like. Wheresuch heating elements are to be used for radiators, it is necessary thatradiation fins or plates must be provided in order to yield efiicientheat radiation. Such plates would have to be braced and stacked to theheating element individually which would render them more subject tobreakage and would be a time consuming and expensive operation.

It is therefore an object of the invention to provide a fin structurefor use with such rod-like heating elements which can be mass producedinexpensively from sheet metal. It is another object of the invention toprovide a structure as outlined above which can easily be assembled tothe heating element and which will provide for eificient heat transferfrom said rod-like heating element.

These and other objects of the invention which will be pointed out ingreater detail hereinafter or which will be apparent to one skilled inthe art upon reading these specifications are accomplished by thatcertain construction and arrangement of parts of which the following isan exemplary embodiment.

Reference is made to the drawings forming a part hereof and in which:

FIGURE 1 is a fragmentary plan view of a structure according to theinvention.

FIGURE 2 is an elevational view of the same.

FIGURE 3 is a cross-sectional view of the same on an enlarged scaletaken on the line 33 of FIGURE 2.

FIGURE 4 is a fragmentary exploded view of the two complementary piecesshowing their relationship to each other.

FIGURE 5 is a fragmentary cross-sectional view taken on the line 55 ofFIGURE 1.

Briefly, in the practice of the invention, the radiation fin structurecomprises two strips of sheet metal which are preferably of a lengthsubstantially equal to the length of the heating element, each of whichis provided with a substantial central longitudinal groove toaccommodate substantially one-half of the heating element so that whensaid two strips are assembled back to back about the heating element,the heating element is seated in the complementary grooves in the twopieces. The two pieces of sheet metal are provided with means forlocking them in assembled condition and are provided with a number offins for enhancing the radiation efiect.

Referring in greater detail to the drawings, the rodlike heating elementis indicated generally at 10. The two pieces constituting the finstructure are indicated generally at 11 and 12. Each of these isdeformed to provide a central longitudinal groove, the groove in themember 11 being indicated at 13 and the groove in the member 12 beingindicated at 14. As will be observed from FIGURE 3, these grooves are ofsuch size and shape that when the pieces 11 and 12 are placed back toback, the complementary portions 13 and 14 form a tubular seat in whichthe heating element 10 is seated. The dimensions are preferably suchthat the assembled pieces 11 and 12 actually grip the heating element.

The fins are struck up from the body of the sheet metal constituting thepieces 11 and 12. Thus, the fins 3,031,171 Patented Apr. 24, 1962 15 arestruck up from the member 11 and the fins 16 are struck up from themember 12. At each place where a fin 15 or 16 is struck up, an apertureis left in the piece 11 or 12 as indicated at 1511 and 16a.

Various arrangements may be provided for locking the pieces 11 and 12together but preferably one of the pieces will be provided with a seriesof locking tongues 17. These locking tongues are also struck up from thebody of the piece 12 and the tongues preferably terminate in a slightlybent up tip as at 17a to facilitate assembly.

It will be observed that the pieces 11 and 12 are identical except forthe fact that the piece 12 is provided with the tongues 17 while thepiece 11 is not. Each of the pieces may be provided with the fasteningflanges as indicated at 18 and 19 provided with the holes 20, 21.

In use, a member 11 and a member 12 are mutually inverted as shown inFIGURE 4 and when they are brought together the tongues 17 of the member12 can pass through the apertures 15a of the member 11 until the twopieces are in contact. Thereupon, by relative movement of the twopieces, the tongues 17 of the member 12 engage over the portions 15b ofthe member 11, as best seen in FIGURES 1, 2 and 5. In this condition,the members 11 and 12 are clamped together and clamped about the heatingelement 10. The flanges 18 and 19 are then in juxtaposition with theholes 20 and 21 in alignment and screws or bolts may be passed throughthe aligned holes, thereby preventing relative longitudinal movement ofthe pieces 11 and 12 to prevent disassembly. The aligned holes 20 and 21may also be used for mounting the assembled heating element on mountingbrackets or the like.

It will be clear that instead of having the two pieces 11 and 12differing by the locking tabs, it is possible to have the two piecesidentical so that they can be made in a single die. This could be doneby having the looking tongues only along one side of each piece so thatwhen the pieces are reversed there will be locking tongues on one pieceon one side of the groove and locking tongues on the other piece on theother side of the groove. A similar result can be obtained by providinglocking tongues adjacent alternate fins on both sides. While suchmodifications may be made, the construction specifically illustrated isconsidered to be preferable.

From the foregoing description, it will be seen that there is provided arelatively simple and inexpensive structure for imparting to a rod-likeor tubular heating element a fin structure to enhance the radiationefliciency thereof. It will be understood that details in theconstruction may be varied considerably without departing from thespirit of the invention. No limitation not clearly set forth in theclaims is therefore intended.

What is claimed as new is:

1. A radiation fin structure for a rod-like heating element comprisingtwo integrally finned strips of sheet metal, each of said strips havinga substantially central longitudinal groove to seat substantially onehalf of a rod-like heating element, such that when said two strips areassembled back to back the said grooves embrace and seat said heatingelement, said fins being struck up from the body of said strips on eachside of said groove, leaving spaced apertures in said strips adjacentsaid fins, and locking tongues struck up from the body of one, at least,of said strips, said tongues extending substantially parallel to thebody of said strip and spaced therefrom by substantially the thicknessof said strip, and opening into some, at least, of said apertures, andintegral means on one, at least, of said strips releasably to lock themtogether in assembled relation about said heating element.

2. A structure according to claim 1, wherein all said locking tonguesare disposed on one of said strips.

3. A structure according to claim 1, wherein there is a tongueassociated with each of said apertures.

4. A structure according to claim 1, wherein means are provided tosecure said strips against relative longitudinal movement whenassembled.

5. A radiation fin device comprising a rod-like heating element and twointegrally finned strips of sheet metal, each of said strips having asubstantially central longitudinal grooveto seat substantially one-halfof said heating element, said two strips being assembled back to backwith the said grooves embracing and seating said heating elements, saidfins being struck up from the body of said strips on each side of saidgroove, leaving spaced apertures in said strips adjacent said fins, andlocking tongues struck up from the body of one, at least, of saidstrips, said tongues extending substantially parallel to the body ofsaid strip and spaced therefrom by substantially the thickness of saidstrip, and opening into some, at least, of said apertures, and integralmeans on one, at least, of said strips releasably locking them togetherin assembled relation about said heating elements.

6. A structure according to claim v5, wherein all said locking tonguesare disposed on one of said strips.

7. A structure according to claim 5, wherein there is a tongueassociated with each of said apertures.

8. A structure according to claim 5, wherein means are provided tosecure said strips agains relative longitudinal movement when assembled.

9. A radiation fin structure for a rod-like heating element comprisingtwo strips of sheet metal, each of said strips having a centrallongitudinal semi-cylindrical groove 4 to seat a rod-like heatingelement, each of said strips having on either side of said groove aseries of integral fins extending normal to the plane of the strip, andtransversely to said groove, and an aperture adjacent each of said fins,one of said strips having a tongue member ad- 1 jacent each of saidapertures and extending substantially parallel to the plane of saidstrip but spaced therefrom by substantially the thickness of said strip,whereby said two strips may be disposed back to back with said tonguesof one strip entering the respective apertures in the other strip andsaid grooves cooperating to provide a seat for a rod-like heatingelement, and said strips may be locked together by a slight relativelongitudinal movement to cause said tongues to engage over adjacentportions of said other strip.

10. A structure according to claim 9, wherein means are provided tosecure said strips against relative longitudinal movement whenassembled.

References Cited in the file .of this patent UNITED STATES PATENTS Dubinet al Aug. 11, 1959

